Post Office Protocol is an Internet Protocol standard (see RFC 1939) that was developed so that individual users can connect to the Mail Exchanger (the mail server) and download their mail. A local client running on your machine with POP3 capability will connect to a Mail Exchanger using TCP on port 110 (or 109 if it uses POP2), download their mail messages, and log out of the server. This allows machines that are not connected to the Internet to still be able to send and receive e-mail.
This is the protocol your Microsoft Outlook or Netscape Messenger uses to pull mail from your Internet Service Provider's mail server.
THIS FILE IS A PLACEHOLDER FOR A FUTURE TUTORIAL